In conventional horizontal rotating electric machines having heat exchangers which are vertically disposed, there is a well-known totally-enclosed electric motor having a configuration as indicated in FIG. 6.
FIG. 6 is a front view illustrating the electric motor viewed from an axis direction of a rotational shaft. A frame 32 is provided around a motor main body 31, and a cooling device 33 is attached to the frame 32. The motor main body 31, the frame 32, and the cooling device 33 are integrally installed in space formed by an outer frame 34 and a base 35, whereby the totally-enclosed electric motor is configured. The electric motor is configured in such a way that a feed-water pipe 36 and a drain pipe 37, which are extended from an outside of the electric motor, are connected to the cooling device 33, and air in the electric motor is cooled by passing cooling water, whereby a temperature of the motor main body 31 is suppressed under a predefined value (for example, refer to Patent Document 1).